If $xy$ is constant
whenever$z$ is constant,
and $y/z$ is constant
whenever$x$ is constant, then show that $xy/z$ is constant.
My work: Write $xy = a$, $y/z = b$. Then
$$xy^2/z = ab, \ \ \ xz = a/b.$$
Remark: This shows up in physics when I'm trying to derive the ideal gas equation from Boyle and Charles' laws ($PV =$ constant and $V/T =$ constant).
z = constantfor first equation and
x = constantfor second equation. I'll add this to the question... Thank you! $\endgroup$